JP2018140621A - Decorative film and method for manufacturing a decorative molded body using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a decorative film for being stuck on a resin molded body by thermoforming which is excellent in scratch resistance, weather resistance, and designability, can exhibit sufficient adhesive strength to the resin molded body, and causes small fading of an embossed pattern after the thermoforming and small damage to the film during the molding, and to provide a decorative molded body using the decorative film.SOLUTION: A decorative film 1 for being stuck on a resin molded body by thermoforming includes: a seal layer (I) 3 made of a resin composition containing a polypropylene resin (A) and an ethylene-α-olefin random copolymer (B) as main components and having a weight ratio of the polypropylene resin (A) to the ethylene-α-olefin random copolymer (B) of 97:3 to 5:95; a layer (II) 2 made of an acrylic resin (C); and an adhesive layer (III) 7 made of an adhesive resin (D) and provided between the seal layer (I) 3 and the layer (II) 2.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a decorative film for sticking by thermoforming on a resin molded body and a method for producing a decorative molded body using the decorative film. Specifically, it is excellent in scratch resistance, weather resistance, and design properties, can exhibit sufficient adhesive strength to the resin molded body, and has little damage given to the film during wrinkle return after molding and molding The present invention relates to a decorative film for sticking to a molded body by thermoforming and a method for producing a decorative molded body using the decorative film.

  In recent years, there has been an increasing demand for decoration techniques that can replace painting due to VOC (volatile organic compound) reduction requirements, and various proposals for decoration techniques have been made.

  In particular, a technique has been proposed in which a decorative film that replaces a coating film is applied to a molded body by vacuum pressure forming or vacuum forming to form a decorative molded product in which the decorative film and the molded body are integrated (for example, Patent Document 1). In recent years, it has attracted particular attention.

  Decorative molding by vacuum pressure forming and vacuum forming has a greater degree of freedom than other decorative moldings typified by insert molding, and the end face of the decorative film is rolled up to the back side of the decorative object. Because it does not occur, it has excellent appearance, and can be thermoformed at a relatively low temperature and low pressure. By applying embossing on the surface of the decorative film, the reproducibility of embossing on the surface of the decorative molded body It has the advantage that it is excellent.

  In such vacuum pressure molding and decorative molding by vacuum molding, acrylic that has excellent properties such as transparency, scratch resistance, weather resistance, and ease of printing, and is a thermoplastic resin that is easy to thermoform. A film made of a resin is widely used as a decorative film. However, since a film made of an acrylic resin softens in a relatively short time when heated, in 3D decorative thermoforming, it is not possible to provide a heating time that can be attached to a decoration object, and the film There was a problem that the adhesive strength between and the object to be decorated was inferior. In response to this problem, the use of acrylic adhesives, urethane adhesives, tackifiers, etc. as layers for improving adhesive strength has been proposed, but these layers are represented by polypropylene resins. However, there is a problem that sufficient adhesive strength cannot be obtained for non-polar resins.

For such problems, a decorative film including an adhesive layer containing a polypropylene resin is applied to a base body (molded body) made of a polypropylene resin, so that the decorative film and the molded body are heat-sealed. (For example, refer to Patent Documents 2 and 3). In the inventions disclosed in Patent Documents 2 and 3, a polypropylene resin is used as the adhesive layer of the decorative film. However, the surface layer on the adhesive layer, and the acrylic layer on the bonding layer and the bulk layer are substantially further provided. It is necessary to provide a layer of resin, polyurethane resin, polycarbonate or the like. In this way, by combining different raw materials, thermoformability such as draw-down property is expressed, and it is possible to ensure thermoformability in a decorative film made of a polypropylene resin that does not contain these different raw materials. However, it was not possible to obtain a decorative molded body having an excellent appearance because holes, wrinkles, and air were easily entrapped on the surface of the molded article on which this was adhered. In particular, when a polyurethane resin is included as a heterogeneous raw material, the polyurethane resin, which is a thermosetting resin, does not melt when heated, and thus easily maintains the form of the film and greatly improves thermoformability, but has a problem of extremely low recyclability. It was.
In addition, decorative thermoforming by vacuum pressure forming and vacuum forming has the advantage that a molded product with a high degree of integrity between the base and the decorative film formed by a process such as injection molding can be obtained, while the decorative film is the base. The surface of the decorative molded body is picked up and scratches on the surface of the decorative molded body tend to cause poor appearance due to the effect of the scratch on the surface of the substrate.

  In addition, decorative thermoforming by vacuum pressure forming and vacuum forming has the advantage that a molded product with a high degree of integrity between the base and the decorative film formed by a process such as injection molding can be obtained, while the decorative film is the base. The surface of the decorative molded body is picked up and scratches on the surface of the decorative molded body tend to cause poor appearance due to the effect of the scratch on the surface of the substrate.

JP 2002-67137 A JP 2013-14027 A JP 2014-124940 A

  In the prior art, the development of a decorative film containing an acrylic resin having good adhesion to a base made of a polypropylene resin has not been achieved yet. In view of the above problems, the object of the present invention is a decorative film containing a base made of polypropylene resin and an acrylic resin capable of realizing high adhesive strength, and scratch resistance, weather resistance, designability, and recycling using the same. The object is to provide a decorative molded body having excellent properties.

  In three-dimensional decorative thermoforming, in order to stick a solid decorative film to a solid resin molded body, it is necessary that the surface of the molded body and the film are sufficiently softened or melted. It is important to add the amount of heat necessary for softening or melting the surface of the molded body and the film, but acrylic resin films soften in a relatively short time. Considering the fact that the film breaks or ramps up due to the pushing up of the molded body in the original decorative thermoforming process or the inflow of air when the vacuum chamber box is returned to the atmospheric pressure leads to poor appearance. As a result, a sealing layer (I) comprising a resin composition containing polypropylene resin (A) and ethylene-α-olefin random copolymer (B) as main components and capable of exhibiting good adhesive strength, acrylic resin A decorative film comprising a layer (II) composed of the adhesive layer (II) and an adhesive layer (III) composed of an adhesive resin (D) between the seal layer (I) and the layer (II) can solve the above problem. The headline and the present invention were completed.

That is, the present invention includes the following.
[1] A decorative film for attaching to a resin molded body by thermoforming,
The decorative film contains a polypropylene resin (A) and an ethylene-α-olefin random copolymer (B) as main components, and the polypropylene resin (A) and an ethylene-α-olefin random copolymer (B). And a weight ratio of 97: 3 to 5:95, a sealing layer (I) made of a resin composition, a layer (II) made of an acrylic resin (C), and a sealing layer (I) and a layer (II) Including an adhesive layer (III) made of an adhesive resin (D),
The polypropylene resin (A) satisfies the following requirement (a1),
The said ethylene-alpha-olefin random copolymer (B) satisfies the following requirements (b1)-(b3), The decorative film characterized by the above-mentioned.
(A1) Melt flow rate (230 ° C., 2.16 kg load) (MFR (A)) exceeds 0.5 g / 10 min.
(B1) The ethylene content [E (B)] is 65% by weight or more.
(B2) The density is 0.850 to 0.950 g / cm ³ .
(B3) Melt flow rate (230 ° C., 2.16 kg load) (MFR (B)) is 0.1 to 100 g / 10 min.
[2] The decorative film according to [1], wherein the ethylene-α-olefin random copolymer (B) satisfies the following requirement (b4).
(B4) Melting peak temperature (Tm (B)) is 30 to 130 ° C. [3] The ethylene-α-olefin random copolymer (B) satisfies the following requirement (b5): The decorative film according to [1] or [2].
(B5) A random copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms.
[4] The adhesive resin (D) is a polyolefin resin having a polar functional group containing at least one hetero atom, and its MFR (230 ° C., 2.16 kg load) (MFR (D)) is 100 g. The decorative film according to any one of [1] to [3], which is a polyolefin resin having a duration of / 10 minutes or less.
[5] The step of preparing the decorative film according to any one of [1] to [4], the step of preparing a resin molded body, and the resin molded body and the decorative film in a chamber box that can be decompressed. A step of setting, a step of depressurizing the interior of the chamber box, a step of heat-softening the decorative film, a step of pressing the decorative film against the resin molded body, and returning or adding the pressure of the decompressed chamber box to atmospheric pressure. The manufacturing method of the decorative molded object characterized by including the step to press.
[6] The method for producing a decorative molded body according to [5], wherein the resin molded body is made of a propylene-based resin composition.

  The decorative film of the present invention exhibits a good adhesive strength to a molded body even when heated for a short time, and therefore does not break or rampage during processing to obtain a decorative molded body with a good appearance. Can do. According to the decorative film of the present invention, excellent design properties can be imparted to the molded body while taking advantage of excellent properties such as transparency, scratch resistance, weather resistance, and ease of printing of the acrylic resin. .

It is a figure which shows an example of the laminated constitution of the decorating film of this invention. It is typical sectional drawing explaining the outline | summary of the apparatus used for the manufacturing method of the decorative molded body of this invention. It is typical sectional drawing explaining a mode that the resin molding and the decorating film were set in the apparatus of FIG. It is typical sectional drawing explaining a mode that the inside of the apparatus of FIG. 2 is heated and pressure-reduced. It is typical sectional drawing explaining a mode that a decorating film is pressed on the resin molding in the apparatus of FIG. It is typical sectional drawing explaining a mode that it returns to atmospheric pressure or pressurizes the inside of the apparatus of FIG. It is a typical sectional view explaining signs that the edge of an unnecessary decoration film was trimmed in the obtained decoration fabrication object. It is a figure which shows an example of the laminated constitution of the obtained decorating molded object.

  In this specification, the decorative film refers to a film for decorating a molded body. Decorative molding refers to molding in which a decorative film and a molded body are attached. Three-dimensional decorative thermoforming is a process of adhering a decorative film and a molded body, and has a step of applying a decorative film at the same time as thermoforming along the adhesive surface of the molded body, In order for this process to suppress air from being caught between the decorative film and the molded body, thermoforming is performed under reduced pressure (vacuum), the heated decorative film is adhered to the molded body, and pressure is applied. It refers to molding, which is a step of bringing in close contact by release (pressurization). Hereinafter, embodiments for carrying out the present invention will be described in detail.

The decorative film in the present invention is a decorative film for sticking on a resin molded body by thermoforming,
The decorative film contains a polypropylene resin (A) and an ethylene-α-olefin random copolymer (B) as main components, and the polypropylene resin (A) and an ethylene-α-olefin random copolymer (B). And a weight ratio of 97: 3 to 5:95, a sealing layer (I) made of a resin composition, a layer (II) made of an acrylic resin (C), and a sealing layer (I) and a layer (II) Including an adhesive layer (III) made of an adhesive resin (D),
The polypropylene resin (A) satisfies the following requirement (a1),
The ethylene-α-olefin random copolymer (B) is a decorative film characterized by satisfying the following requirements (b1) to (b3).
(A1) Melt flow rate (230 ° C., 2.16 kg load) (MFR (A)) exceeds 0.5 g / 10 min.
(B1) The ethylene content [E (B)] is 65% by weight or more.
(B2) The density is 0.850 to 0.950 g / cm ³ .
(B3) Melt flow rate (230 ° C., 2.16 kg load) (MFR (B)) is 0.1 to 100 g / 10 min.

[Sealing layer (I)]
The decorative film of the present invention includes a seal layer (I) made of a resin composition composed of a polypropylene resin (A) and an ethylene-α-olefin random copolymer (B). The seal layer (I) is a layer in contact with the resin molded body (base) during three-dimensional decorative thermoforming. By providing the sealing layer (I), sufficient adhesive strength is exhibited even if the film heating time during the three-dimensional decorative thermoforming is short, and scratches on the substrate surface can be made inconspicuous.

[Polypropylene resin (A)]
The polypropylene resin (A) in the present invention is a propylene homopolymer (homopolypropylene), a propylene-α-olefin copolymer (random polypropylene), a propylene block copolymer (block polypropylene), or any other type of propylene-based resin. Polymers or combinations thereof can be selected. The propylene polymer preferably contains 50 mol% or more of polymer units derived from a propylene monomer. It is preferable that the propylene-based polymer does not contain a polymer unit derived from a polar group-containing monomer.

(A1) Melt flow rate (MFR (A))
The melt flow rate (230 ° C., 2.16 kg load) MFR (A) of the polypropylene resin (A) contained in the sealing layer (I) needs to exceed 0.5 g / 10 minutes, preferably 1 g. / 10 minutes or more, more preferably 2 g / 10 minutes or more. Within the above range, the relaxation during the three-dimensional decorative thermoforming sufficiently proceeds and sufficient adhesive strength can be exhibited, and scratches on the substrate are less noticeable. Although there is no restriction | limiting in the upper limit of MFR (A), It is preferable that it is 100 g / 10min or less. Within the above range, the adhesive strength is not deteriorated due to a decrease in physical properties.

  In this specification, the MFR of the polypropylene resin and the polypropylene resin composition described later was measured in accordance with ISO 1133: 1997 Conditions M under the conditions of 230 ° C. and 2.16 kg load. The unit is g / 10 minutes.

(A2) Melting peak temperature (Tm (A))
The melting peak temperature of the polypropylene resin (A) (DSC melting peak temperature, sometimes referred to as “melting point” in this specification) (Tm (A)) is preferably 110 ° C. or higher, and 115 ° C. or higher. It is more preferable that it is 120 degreeC or more. Within the above range, the moldability during three-dimensional decorative thermoforming is good. Although there is no restriction | limiting in the upper limit of melting peak temperature, it is preferable that it is 170 degrees C or less, and sufficient adhesive strength can be exhibited as it is the said range.

  The polypropylene resin (A) in the present invention can be a resin polymerized by a Ziegler catalyst, a metallocene catalyst, or the like. That is, the polypropylene resin (A) can be a Ziegler catalyst propylene polymer or a metallocene catalyst propylene polymer.

[Ethylene-α-olefin random copolymer (B)]
The ethylene-α-olefin random copolymer (B) used as an essential component in the seal layer (I) of the present invention has the following characteristics (b1) to (b3), preferably (b4) and / or (b5). ).

(B1) Ethylene content [E (B)]
The ethylene content [E (B)] of the ethylene-α-olefin random copolymer (B) of the present invention is 65% by weight or more based on the total amount of the ethylene-α-olefin random copolymer (B). Is preferably 68% by weight or more, more preferably 70% by weight or more. Within the above range, sufficient adhesive strength can be exhibited during three-dimensional decorative thermoforming, and the heating time of the film can be shortened. The upper limit of the ethylene content [E (B)] is not particularly limited, but is preferably 95% by weight or less.

(Calculation method of ethylene content [E (B)])
The ethylene content [E (B)] of the ethylene-α-olefin random copolymer (B) can be determined from the integrated intensity obtained by ¹³ C-NMR measurement.

(Calculation method 1 (binary system))
First, a method for calculating the ethylene content [E (B)] in a binary copolymer composed of two kinds of repeating units will be described. In this case, the ethylene content of the ethylene-α-olefin binary copolymer can be determined by (Formula-1-1) and (Formula-1-2).
Ethylene content (mol%) = IE × 100 / (IE + IX) (Formula-1-1)
Ethylene content [E (B)] (wt%) = [ethylene content (mol%) × ethylene molecular weight] × 100 / [ethylene content (mol%) × ethylene molecular weight + α-olefin content (mol%) × α− Molecular Weight of Olefin] (Formula-1-2)

Here, IE and IX are integral intensities for ethylene and α-olefin, respectively, and can be obtained by the following (formula-2) and (formula-3).
_{IE = (I ββ + I γγ} + I βδ + I γδ + I δδ) / 2 + (I αγ + I αδ) / 4 ··· ( Formula -2)
_{IX = I αα + (I αγ} + I αδ) / 2 ··· ( wherein -3)
Here, the subscript symbol I on the right side represents carbon described in the following structural formulas (a) to (d). For example, αα represents a methylene carbon based on an α-olefin chain, and I _αα represents an integrated intensity of a signal of methylene carbon based on an _α -olefin chain.

In structural formula (d), n represents an odd number of 1 or more.
Below, the integrated intensity | strength used for (Formula-2) and (Formula-3) for every alpha-olefin of an ethylene-alpha-olefin binary system copolymer is demonstrated.

<In the case of ethylene-propylene copolymer>
When the α-olefin is propylene, the following integrated intensity value is substituted into (Formula-2) and (Formula-3) to determine the ethylene content [E (B)].
I _ββ = I _25.0-24.2
I γγ = I _30.8-30.6
I _βδ = I _27.8-26.8
I _γδ = I _30.6-30.2
I _δδ = I _30.2-28.0
I αα = I _48.0-43.9
I _αγ + I _αδ = I _39.0-36.2

Here, the numerical value of the subscript I on the right side indicates the range of chemical shift. For example, I _39.0-36.2 indicates the integrated intensity of the ¹³ C signal detected between 39.0 ppm and 36.2 ppm.
The chemical shift sets the ¹³ C signal of hexamethyldisiloxane to 1.98 ppm, and the chemical shift of the signal due to the other ¹³ C is based on this. Similarly to the ethylene-propylene copolymer, the ethylene-1-butene copolymer, the ethylene-1-hexene copolymer, and the ethylene-1-octene copolymer will be described below.

<In the case of ethylene-1-butene copolymer>
When the α-olefin is 1-butene, the following integrated intensity value is substituted into (Formula-2) and (Formula-3) to determine the ethylene content [E (B)].
_I ββ = I _24.6-24.4
I γγ = I _30.9-30.7
I _βδ = I _27.8-26.8
I _γδ = I _30.5-30.2
I _δδ = I _30.2-28.0
I αα = I _39.3-38.1
I _αγ + I _αδ = I _34.5-33.8

<In case of ethylene-1-hexene copolymer>
When the α-olefin is 1-hexene, the value of the following integrated intensity is substituted into (Formula-2) and (Formula-3) to obtain the ethylene content [E (B)].
_I ββ = I _24.5-24.4
I γγ = I _31.0-30.8
I _βδ = I _27.5-27.0
I _γδ = I _30.6-30.2
I _δδ = I _30.2-28.0
I αα = I _40.0-39.0
I _αγ + I _αδ = I _35.0-34.0

<In the case of ethylene-1-octene copolymer>
When the α-olefin is 1-octene, the βδ signal and the αγ + αδ signal are overlapped with the methylene carbon of the hexyl branch based on 1-octene (the following structural formulas 5B6 and 6B6).
I _βδ + I _5B6 = I _27.6-26.7
I _αγ + I _αδ + I _6B6 = I _35.0-34.0

Therefore, I _βδ corrected for the overlap of _5B6 and _6B6 and I _αγ + I _αδ are substituted, and the integral strength shown below is substituted into (Equation-2) and (Equation-3), and the ethylene content [E (B )].
_I ββ = I _{24.7-24.2
I γγ + I γδ + I δδ} = I 32.0-28.0
_Iβδ = 2/3 × I _27.6-26.7
I αα = I _40.8-39.6
I _αγ + I _αδ = I _βδ + 2 × I _ββ

(Calculation method 2 (ternary system))
Next, a method for calculating the ethylene content [E (B)] in a ternary copolymer composed of three types of repeating units will be described. For example, the ethylene content of the ethylene-propylene-butene ternary copolymer can be determined by the following (formula-4-1) and (formula-4-2).
Ethylene content (mol%) = IE × 100 / (IE + IP + IB) (Formula-4-1)
Ethylene content [E (B)] (weight%) = [ethylene content (mol%) × ethylene molecular weight] × 100 / [ethylene content (mol%) × ethylene molecular weight + propylene content (mol%) × propylene molecular weight + Butene content (mol%) × butene molecular weight] (formula-4-2)
Here, IE, IP, and IB are integral intensities for ethylene, propylene, and butene, respectively, and can be obtained by (Equation-5), (Equation-6), and (Equation-7).
_{IE = (I ββ + I γγ} + I βδ + I γδ + I δδ) / 2 + (I αγ (P) + I αδ (P) + I αγ (B) + I αδ (B)) / 4 ··· ( wherein -5)
IP = 1/3 × [I _{CH3 (P)} + I _{CH (P)} + I _{αα (PP)} + 1/2 × (I _{αα ( PB)} + I _{αγ (P)} + I _{αδ (P)} )] _(formula− 6)
IB = 1/4 × [(I _{CH3 (B)} + I _{CH (B)} + I _2B2 + I _{αα (BB)} ) + 1/2 × (I _{αα ( PB)} + I _{αγ (B)} + I _{αδ (B)} )] (Formula-7)
Here, the subscript (P) means a signal based on propylene-derived methyl group branching, and similarly, (B) means a signal based on butene-derived ethyl group branching.
Αα (PP) means a methylene carbon signal based on a propylene chain, similarly αα (BB) means a methylene carbon signal based on a butene chain, and αα (PB) means a methylene carbon based on a propylene-butene chain. Signal.

Here, since the γγ signal overlaps with the tail of the methine carbon CH (PPE) of central propylene aligned with propylene-propylene-ethylene, it is difficult to separate the γγ signal.
The γγ signal appears in the structural formula (c) with two ethylene chains, and (Formula-8) holds for the integrated intensity of γγ derived from ethylene and the integrated intensity of βδ in the structural formula (c).
I _βδ (Structural Formula (c)) = 2 × I _γγ (Formula-8)
Further, βδ appears in the structural formula (d) having three or more ethylene chains, and the integrated strength of βδ in the structural formula (d) is equal to the integrated strength of γδ (Formula-9).
I _βδ (Structural Formula (d)) = I _γδ (Formula-9)
Therefore, βδ based on the structural formula (c) and the structural formula (d) is obtained by (Formula-10).
I _βδ = I _βδ (Structural Formula (c)) + I _βδ (Structural Formula (d)) = 2 × I _γγ + I _γδ (Formula-10)
_{That, I γγ = (I βδ -I} γδ) / 2 ··· ( wherein -10 ')
Therefore, when (Expression-10 ′) is substituted into (Expression-5), IE can be replaced with (Expression-11).
_{IE = (I ββ + I δδ} ) / 2 + (I αγ (P) + I αδ (P) + I αγ (B) + I αδ (B) + 3 × I βδ + I γδ) / 4 ··· ( wherein -11)
Here, the βδ signal corrects the overlap of ethyl branches based on 1-butene, and becomes (Equation-12).
_{I βδ = I αγ (P)} + I αδ (P) + I αγ (B) + I αδ (B) -2 × I ββ ··· ( wherein -12)
From (Formula-11) and (Formula-12), IE becomes (Formula-13).
IE = I _δδ / 2 + I _γδ / 4-I _ββ + I _{αγ (P)} + I _{αδ (P)} + I _{αγ (B)} + I _{αδ (B)} (Formula-13)
Substitute the following into (Formula-13), (Formula-6), and (Formula-7) to determine the ethylene content.
I _ββ = I _25.2-23.8
I _γδ = I _30.4-30.2
I _δδ = I _30.2-29.8
I _{αγ (P)} + I _{αδ (P)} = I _39.5-37.3
I _{αγ (B)} + I _{αδ (B)} = I _34.6-33.9
I _{CH3 (P)} = I _22.6-19.0
I _{CH (P)} = I _29.5-27.6 + I _31.2-30.4 + I _33.4-32.8
I _{αα (PP)} = I _48.0-45.0
I _{CH3 (B)} = I _11.4-10.0
I _{CH (B)} = I _35.5-34.7 + I _37.4-36.8 + I _39.7-39.6
I _{αα (BB)} = I _40.3-40.0
I _{αα (PB)} = I _44.2-42.0
I _2B2 = I _26.7-26.4

In addition, the following five references were referred to the assignment of each signal.
Macromolecules, Vol. 10, NO. 4, 1977,
Macromolecules, Vol. 36, no. 11, 2003,
Analytical Chemistry, Vol. 76, no. 19, 2004,
Macromolecules, 2001, 34, 4757-4767,
Macromolecules, Vol. 25, no. 1,1992

  Even if the α-olefin of the ethylene-α-olefin random copolymer is a case other than the case described above, each signal can be assigned and the ethylene content can be obtained in the same manner as described above.

(B2) the density of the density ethylene -α- olefin random copolymer (B) is required to be 0.850~0.950g / cm ^3, preferably 0.855~0.900g / cm ³ More preferably, it is 0.86-0.890 g / cm < ³ >. Within the above range, sufficient adhesive strength is exhibited during three-dimensional decorative thermoforming, and film formability is also good.

(B3) Melt flow rate (MFR (B))
The melt flow rate (230 ° C., 2.16 kg load) MFR (B) of the ethylene-α-olefin random copolymer (B) needs to be 0.1 to 100 g / 10 min, preferably 0. 0.5 to 50 g / 10 min, more preferably 1 to 30 g / 10 min. Within the above range, the effect of making the scratches on the substrate less noticeable is high.

(B4) Melting peak temperature (Tm (B))
The melting temperature peak (DSC melting peak temperature) Tm (B) of the ethylene-α-olefin random copolymer (B) is preferably 30 to 130 ° C, more preferably 35 to 120 ° C, still more preferably 40. ~ 110 ° C. When it is in the above range, sufficient adhesive strength can be exhibited during three-dimensional decorative thermoforming.

(B5) α-olefin of ethylene-α-olefin random copolymer (B) The ethylene-α-olefin random copolymer (B) is a copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms. Preferably there is. Specific examples of the α-olefin having 3 to 20 carbon atoms include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene and 1-decene. 1-dodecene, 1-tetradecene, 1-hexadecene, 1-eicocene and the like. Of these, propylene, 1-butene, 1-hexene and 1-octene are particularly preferably used.

  Such an ethylene-α-olefin random copolymer (B) is produced by copolymerizing each monomer in the presence of a catalyst. Specifically, the ethylene-α-olefin random copolymer (B) uses a gas phase method, a solution method, a high pressure method using a catalyst such as a Ziegler catalyst, a Philips catalyst, or a metallocene catalyst as an olefin polymerization catalyst. It can be produced by copolymerizing ethylene and an α-olefin such as propylene, 1-butene, 1-hexene, 4-methyl-1-pentene and 1-octene by a process such as a slurry method.

In addition, the ethylene-α-olefin random copolymer (B) used for the seal layer (I) of the present invention can be used alone or in combination of two or more without departing from the effects of the present invention.
As commercial products of such ethylene-α-olefin random copolymers, Kernel Series manufactured by Nippon Polyethylene Co., Ltd., Tuffmer P Series, Tuffmer A Series manufactured by Mitsui Chemicals, Inc., Engage EG Series manufactured by DuPont Dow, etc. Is mentioned.

[Resin composition]
The resin composition constituting the seal layer (I) contains a polypropylene resin (A) and an ethylene-α-olefin random copolymer (B) as main components, and the polypropylene resin (A) and ethylene- It may be a mixture or melt-kneaded product with the α-olefin random copolymer (B), and is a sequential polymer of the polypropylene resin (A) and the ethylene-α-olefin random copolymer (B). Also good.

  In the resin composition of the sealing layer (I), the weight ratio ((A) :( B)) of the polypropylene resin (A) and the ethylene-α-olefin random copolymer (B) is 97: 3 to 5: It is necessary to be selected in the range of 95, preferably 95: 5 to 10:90, more preferably 93: 7 to 20:80. Within the above range, sufficient adhesive strength can be exhibited during three-dimensional decorative thermoforming, the heating time of the film can be shortened, and the adhesion between the sealing layer (I) and the layer (II) is good. is there.

  The resin composition constituting the seal layer (I) may contain additives, fillers, other resin components, and the like. However, the total amount of additives, fillers, and other resin components is preferably 50% by weight or less based on the resin composition.

  Additives can be used for polypropylene resins such as antioxidants, neutralizers, light stabilizers, UV absorbers, crystal nucleating agents, antiblocking agents, lubricants, antistatic agents, metal deactivators, etc. Various known additives can be blended.

  Examples of antioxidants include phenolic antioxidants, phosphite antioxidants, and thio antioxidants. Examples of the neutralizing agent include higher fatty acid salts such as calcium stearate and zinc stearate. Examples of the light stabilizer and the ultraviolet absorber include hindered amines, benzotriazoles, and benzophenones.

  Examples of the crystal nucleating agent include amide nucleating agents such as aromatic carboxylic acid metal salts, aromatic phosphoric acid metal salts, sorbitol derivatives, and metal salts of rosin. Among these crystal nucleating agents, pt-butyl aluminum benzoate, 2,2′-methylenebis (4,6-di-t-butylphenyl) sodium phosphate, 2,2′-methylenebisphosphate (4 , 6-Di-t-butylphenyl) aluminum, bis (2,4,8,10-tetra-tert-butyl-6-hydroxy-12H-dibenzo [d, g] [1,2,3] dioxaphospho Syn-6-oxide) aluminum hydroxide salt and organic compound complex, p-methyl-benzylidene sorbitol, p-ethyl-benzylidene sorbitol, 1,2,3-trideoxy-4,6: 5,7-bis- [ (4-Propylphenyl) methylene] -nonitol, sodium salt of rosin and the like.

  Examples of the lubricant include higher fatty acid amides such as stearic acid amide. Examples of the antistatic agent include fatty acid partial esters such as glycerin fatty acid monoester. Examples of the metal deactivator include triazines, phosphones, epoxies, triazoles, hydrazides, oxamides and the like.

  As a filler, various well-known fillers which can be used for polypropylene resin, such as an inorganic filler and an organic filler, can be mix | blended. Examples of the inorganic filler include calcium carbonate, silica, hydrotalcite, zeolite, aluminum silicate, magnesium silicate, glass fiber and carbon fiber. Examples of the organic filler include crosslinked rubber fine particles, thermosetting resin fine particles, and thermosetting resin hollow fine particles.

  Examples of other resin components include modified polyolefin, petroleum resin, and other thermoplastic resins.

  The method for producing the resin composition is a method in which a polypropylene resin (A), an ethylene-α-olefin random copolymer (B), an additive, a filler, other resin components, and the like are melt-kneaded, a polypropylene resin A method of dry blending an ethylene-α-olefin random copolymer (B) into a melt-kneaded mixture of (A) and additives, fillers and other resin components, and a polypropylene resin (A) as an ethylene-α-olefin. In addition to the random copolymer (B), it can be produced by a method of dry blending a master batch in which additives, fillers, other resin compositions and the like are dispersed in a carrier resin at a high concentration.

[Layer (II)]
The decorative film of the present invention includes a layer (II) made of an acrylic resin (C). By including the layer (II) made of the acrylic resin (C), the acrylic resin has excellent design characteristics utilizing the excellent properties such as transparency, scratch resistance, weather resistance, and ease of printing. A decorative molded body can be obtained.

[Acrylic resin (C)]
Examples of the acrylic resin (C) in the present invention include acrylic resins such as polymethyl methacrylate, polyethyl methacrylate, polybutyl methacrylate, methyl methacrylate-butyl methacrylate copolymer, and methyl methacrylate-styrene copolymer. Furthermore, the above-described mixed resin of acrylic resin and thermoplastic polyurethane resin, or the above-described mixed resin of acrylic resin and acrylic rubber can be used.

  Acrylic resin (C) contains general additives such as stabilizers, lubricants, processing aids, impact aids, fillers, colorants, matting agents, UV absorbers and the like as necessary. be able to. As the above-mentioned acrylic resin, a commercial name “Acripet” manufactured by Mitsubishi Rayon Co., Ltd., a trade name “Sumipex” manufactured by Sumitomo Chemical Co., Ltd., and the like can be suitably used.

[Adhesive layer (III)]
The decorative film of the present invention includes an adhesive layer (III) made of an adhesive resin (D). By providing an adhesive layer made of an adhesive resin (D), a layer (II) made of an acrylic resin and a seal layer made of a polypropylene resin (A) and an ethylene-α-olefin random copolymer (B) ( I) can be bonded without using an organic solvent.

[Adhesive resin (D)]
The adhesive resin (D) is a resin that exhibits adhesion to both the polypropylene resin (A) and the resin composition comprising the ethylene-α-olefin random copolymer (B) and the acrylic resin (C). If there is no particular limitation, it is preferably a polyolefin resin having a polar functional group containing a hetero atom.

  Examples of the polar functional group containing a hetero atom include an epoxy group, a carbonyl group, an ester group, an ether group, a hydroxy group, a carboxy group or a metal salt thereof, an alkoxy group, an aryloxy group, an acyl group, an acyloxy group, an acid anhydride group, Examples thereof include an amino group, an imide group, an amide group, a nitrile group, a thiol group, a sulfo group, an isocyanate group, and a halogen group. Specific examples of the polyolefin having such a polar functional group include: acid-modified polypropylene such as maleic anhydride-modified polypropylene, maleic acid-modified polypropylene, and acrylic acid-modified polypropylene; ethylene / vinyl chloride copolymer, ethylene / vinylidene chloride copolymer Polymer, ethylene / acrylonitrile copolymer, ethylene / methacrylonitrile copolymer, ethylene / vinyl acetate copolymer, ethylene / acrylamide copolymer, ethylene / methacrylamide copolymer, ethylene / acrylic acid copolymer, ethylene / Methacrylic acid copolymer, ethylene / maleic acid copolymer, ethylene / methyl acrylate copolymer, ethylene / ethyl acrylate copolymer, ethylene / isopropyl acrylate copolymer, ethylene / butyl acrylate copolymer , Ethile / Isobutyl acrylate copolymer, ethylene / 2-ethylhexyl acrylate copolymer, ethylene / methyl methacrylate copolymer, ethylene / ethyl methacrylate copolymer, ethylene / isopropyl methacrylate copolymer, ethylene / methacrylic acid Butyl copolymer, ethylene / isobutyl methacrylate copolymer, ethylene / 2-ethylhexyl methacrylate copolymer, ethylene / maleic anhydride copolymer, ethylene / ethyl acrylate / maleic anhydride copolymer, ethylene / acrylic Acid metal salt copolymer, ethylene / methacrylic acid metal salt copolymer, ethylene / vinyl acetate copolymer or saponified product thereof, ethylene / vinyl propionate copolymer, ethylene / glycidyl methacrylate copolymer, ethylene / Ethyl acrylate / glycidyl methacrylate Copolymers, ethylene or α- olefin / vinyl monomer copolymers such as ethylene / vinyl acetate / glycidyl methacrylate copolymer; and chlorinated polyolefins such as chlorinated polypropylene chlorinated polyethylene. Moreover, these resin may be used independently and may be mixed with 2 or more types. Furthermore, you may mix other resin or rubber | gum, a tackifier, various additives, etc. as needed.

  Examples of the other resin or rubber include poly α-olefin such as polypentene-1 and polymethylpentene-1, ethylene such as propylene / butene-1 copolymer, and α-olefin / α-olefin copolymer, Ethylene such as ethylene / propylene / 5-ethylidene-2-norbornene copolymer or α-olefin / α-olefin / diene monomer copolymer, polydiene copolymer such as polybutadiene and polyisoprene, styrene / butadiene random copolymer Polymer, vinyl monomer / diene monomer random copolymer such as styrene / isoprene random copolymer, vinyl monomer such as styrene / butadiene / styrene block copolymer, styrene / isoprene / styrene block copolymer / Diene monomer / Vinyl monomer block copolymer , Hydrogenation (styrene / butadiene random copolymer), hydrogenation (vinyl monomer / diene monomer random copolymer), hydrogenation (styrene / butadiene random copolymer), hydrogenation (styrene / butadiene) / Styrene block copolymer), hydrogenation (styrene / isoprene / styrene block copolymer) and other hydrogenation (vinyl monomer / diene monomer / vinyl monomer block copolymer), acrylonitrile / butadiene / Styrene graft copolymer, vinyl monomer / diene monomer / vinyl monomer graft copolymer such as methyl methacrylate / butadiene / styrene graft copolymer, polyvinyl chloride, polyvinylidene chloride, polyacrylonitrile, poly Vinyl acetate, polyethyl acrylate, polybutyl acrylate, polymethyl methacrylate, poly Vinyl polymers such as styrene, vinyl / acrylonitrile copolymers chloride, vinyl chloride / vinyl acetate copolymer, acrylonitrile / styrene copolymer, and vinyl copolymers such as methyl methacrylate / styrene copolymer.

  Examples of the tackifier include rosin resins (gum rosin, tall oil rosin, wood rosin, hydrogenated rosin, disproportionated rosin, polymerized rosin, maleated rosin, rosin ester, etc.), terpene phenol resin, terpene resin ( polymers such as α-pinene, β-pinene and limonene), aromatic hydrocarbon-modified terpene resins, petroleum resins (aliphatic, alicyclic, aromatic, etc.), coumarone / indene resins, styrene resins, Examples thereof include phenol resins (alkyl phenol, phenol xylene formaldehyde, rosin-modified phenol resin, etc.), xylene resins and the like, and these can be used alone or in combination of two or more. Among these, from the viewpoint of thermal stability, rosin resin, terpene phenol resin, terpene resin, aromatic hydrocarbon modified terpene resin, petroleum resin, hydrogenated petroleum resin are preferable, and are compatible with the modified polyolefin resin of the present invention. And since it can contribute also to adhesion | attachment with polar resin, rosin-type resin and terpene phenol resin are especially preferable.

  Examples of the additives include antioxidants, metal deactivators, phosphorus-based processing stabilizers, UV absorbers, UV stabilizers, fluorescent brighteners, metal soaps, antacid adsorbents, and crosslinking agents. , Chain transfer agents, nucleating agents, lubricants, plasticizers, fillers, reinforcing materials, pigments, dyes, flame retardants, antistatic agents and the like, and may be added within a range not impairing the effects of the present invention.

  As a commercial product of polyolefin resin having a polar functional group, a product name “Admer” manufactured by Mitsui Chemicals, Inc., a product name “Modic” manufactured by Mitsubishi Chemical Corporation, and “Yumex” manufactured by Sanyo Kasei Co., Ltd. can be suitably used.

Melt flow rate (MFR (D))
The melt flow rate (230 ° C., 2.16 kg load) MFR (D) of the adhesive resin (D) is preferably 100 g / 10 min or less, more preferably 50 g / 10 min or less, and further preferably 20 g / 10 min or less. is there. By setting MFR (D) to be equal to or less than the above value, the adhesive layer (III) made of the adhesive resin (D) can be laminated on the seal layer (I) by extrusion molding. MFR (D) is preferably 0.1 g / 10 min or more, more preferably 0.3 g / 10 min or more. By making MFR (D) more than the above value, co-extrusion molding of a resin composition comprising a polypropylene resin (A) and an ethylene-α-olefin random copolymer (B) and an adhesive resin (D) In this case, it is possible to suppress the occurrence of problems such as the occurrence of rough interface at the lamination interface or the lamination of the adhesive resin (D) up to the film end.

[Decorative film]
The decorative film in the present invention includes a sealing layer (I) containing a resin composition comprising a polypropylene resin (A) and an ethylene-α-olefin random copolymer (B), and a layer comprising an acrylic resin (C) ( The adhesive layer (III) composed of II) and the adhesive resin (D) is included in the order of seal layer (I) / adhesive layer (III) / layer (II). The decorative film can take various configurations in addition to the sealing layer (I), the adhesive layer (III), and the layer (II). That is, even if the decorative film is a three-layer film composed of the seal layer (I), the adhesive layer (III) and the layer (II), the seal layer (I), the adhesive layer (III) and the layer (II) It may be a multilayer film of four or more layers composed of other layers. The seal layer (I) is adhered along the resin molded body (base). In addition, the decorative film may have a surface with embossing, embossing, printing, sand plasting, scratching, or the like.

  The decorative film has a large degree of freedom in shape, and since the seam does not occur because the end surface of the decorative film is rolled up to the back side of the object to be decorated, it is excellent in appearance, and furthermore, the surface of the decorative film is given wrinkles or the like Can express various textures. For example, when a texture such as embossing is applied to the resin molded body, three-dimensional decorative thermoforming may be performed using a decorative film provided with embossing. For this reason, it is very difficult and expensive to perform molding with a molded body mold that gives embossing, that is, a molded body mold is required for each embossing pattern, and that complicated embossing is applied to a curved surface mold. Thus, it is possible to obtain a decorative molded body to which various patterns of embossing can be easily applied.

  In addition to the sealing layer (I), the adhesive layer (III) and the layer (II), the multilayer film includes a surface layer, a surface decoration layer, a printing layer, a light shielding layer, a colored layer, a base material layer, a barrier layer, A tie layer layer or the like that can be provided between the layers can be included.

  In the multilayer film, the layers other than the sealing layer (I), the adhesive layer (III) and the layer (II) are preferably layers made of a thermoplastic resin, more preferably a layer made of a polypropylene resin. As long as the layers other than the seal layer (I), the adhesive layer (III) and the layer (II) can be distinguished from the seal layer (I), the adhesive layer (III) and the layer (II), the polypropylene resin constituting the layers Is not particularly limited. Each layer is preferably a layer that does not contain a thermosetting resin. By using a thermoplastic resin, recyclability is improved, and by using a polypropylene-based resin, complication of the layer structure can be suppressed, and the recyclability is further improved.

  When the decorative film is a multilayer film of four or more layers, the sealing layer (I) / adhesive layer (III) / layer (II) / other layers (including a plurality of layers) from the sticking surface side of the resin molded body Alternatively, a configuration of sealing layer (I) / other layers (including a plurality of layers) / adhesive layer (III) / layer (II) / other layers (including a plurality of layers) may be mentioned.

  Drawing 1 (a) and (b) is an explanatory view which illustrates typically the section of the embodiment of a decoration film. In FIGS. 1 (a) and (b), the arrangement of the sealing layer (I), the adhesive layer (III), and the layer (II) is specified and explained for easy understanding. Is not construed as being limited to these examples. In the present specification, reference numeral 1 in the drawing denotes a decorative film, reference numeral 2 denotes a layer (II), reference numeral 3 denotes a sealing layer (I), reference numeral 4 denotes a printing layer (IV), reference numeral 5 denotes a resin molded body, and reference numeral 7 denotes The adhesive layer (III) is shown. The decorative film in FIG. 1A is composed of a seal layer (I), an adhesive layer (III), and a layer (II). As shown in FIG. 8, the seal layer (I) is pasted on the surface of the resin molded body 5. The adhesive layer (III) is laminated on the sealing layer (I), and the layer (II) is laminated on the adhesive layer (III) in this order. The decorative film in FIG. 1B is composed of a sealing layer (I), an adhesive layer (III), a layer (II), and a printed layer (IV) made of a polypropylene resin. As shown in FIG. The seal layer (I) is adhered to the surface of 5, the adhesive layer (III) on the seal layer (I), the layer (II) on the adhesive layer (III), and the print on the layer (II) Layer (IV) is laminated in this order.

  The decorative film of the present invention has a thickness of preferably about 20 μm or more, more preferably about 50 μm or more, and further preferably about 80 μm or more. By setting the thickness of the decorative film to such a value or more, the effect of imparting design properties is improved, the stability at the time of molding is improved, and a better decorative molded body can be obtained. On the other hand, the thickness of the decorative film is preferably about 2 mm or less, more preferably about 1.2 mm or less, and still more preferably about 0.8 mm or less. By making the thickness of the decorative film below such a value, the time required for heating at the time of thermoforming is shortened so that productivity is improved and it becomes easy to trim unnecessary portions.

  In the decorative film of the present invention, the ratio of the thickness of the sealing layer (I) in the total thickness of the decorative film is preferably 1 to 69%, and the ratio of the thickness of the adhesive layer (III) is preferably 1 The ratio of the thickness of the layer (II) is preferably 30 to 98%. If the ratio of the thickness of the sealing layer (I) to the whole decorative film is within the above range, sufficient adhesive strength can be exhibited. Moreover, if the ratio of the thickness of the contact bonding layer (III) to the whole decoration film is the range of said value, delamination of a layer (I) and a layer (III) can be suppressed. Moreover, if the ratio of the thickness of the layer (II) which occupies for the whole decoration film is the said value range, it can avoid that the thermoformability of a decoration film becomes inadequate.

[Manufacture of decorative film]
The decorative film of the present invention can be produced by various known forming methods.
For example, a sealing layer (I) containing a resin composition comprising a polypropylene resin (A) and an ethylene-α-olefin random copolymer (B), an adhesive layer (III) comprising an adhesive resin (D), and an acrylic resin Method of coextrusion molding (II) made of resin (C) (and other layers), coextrusion molding of seal layer (I) and adhesive layer (III) and other layers, and extrusion molding in advance On the surface of the layer (II) made of the acrylic resin (C), a heat lamination method in which heat and pressure are applied so that the layer (II) and the adhesive layer (III) are in contact with each other. A layer (II) composed of an acrylic resin (C), and a seal layer comprising a resin composition composed of a polypropylene resin (A) extruded in advance and an ethylene-α-olefin random copolymer (B) ( I) is bonded to the adhesive layer (III) on the surface of the layer (II) made of the acrylic resin (C), which is formed by a dry lamination method and a wet lamination method in which the adhesive layer (III) is pasted together. And an extrusion lamination method in which a sealing resin (I) containing a resin composition comprising a polypropylene resin (A) and an ethylene-α-olefin random copolymer (B) is melt-extruded, or an acrylic resin (C And a sealing layer (I) comprising a resin composition comprising a polypropylene resin (A) and an ethylene-α-olefin random copolymer (B) which have been extruded in advance. For example, a sand lamination method in which the adhesive layer (III) is used for adhesion. As a device for forming the decorative film, a known coextrusion T-die molding machine or a known laminate molding machine can be used.

  As a method of cooling the molten decorative film extruded from the die, a method of bringing the molten decorative film into contact with one cooling roll through the air discharged from the air knife unit or the air chamber unit, There is a method of cooling by pressure bonding with a plurality of cooling rolls.

  In the case of imparting gloss to the decorative film of the present invention, a method is used in which a mirror-like cooling roll is surface-transferred to the design surface of the decorative film and mirror-finished.

  Furthermore, the surface of the decorative film of the present invention may have a textured shape. Such a decorative film is a method in which a resin in a molten state extruded from a die is directly pressure-bonded with a roll having a concavo-convex shape and a smooth roll to transfer the concavo-convex shape to a surface, Can be manufactured by a method such as surface transfer by pressing with a heated roll and a smooth cooling roll. Examples of the wrinkle shape include satin finish, animal skin tone, hairline tone, and carbon tone.

  The decorative film of the present invention may be heat-treated after film formation. Examples of the heat treatment method include a method of heating with a hot roll, a method of heating with a heating furnace or a far infrared heater, a method of blowing hot air, and the like.

[Decorative molded body]
As the molded article (decoration target) to be decorated in the present invention, various molded articles (hereinafter sometimes referred to as “substrate”) preferably made of a polypropylene resin or a polypropylene resin composition can be used. . The molding method of the molded body is not particularly limited, and examples thereof include injection molding, blow molding, press molding, and extrusion molding.

  Since the polypropylene resin is nonpolar, it is a hardly adhesive polymer, but the decorative film in the present invention is composed of a polypropylene resin (A) and an ethylene-α-olefin random copolymer (B). By including the sealing layer (I) containing the resin composition, the decorative object made of polypropylene resin and the decorative film stick to each other, thereby exhibiting very high adhesive strength and attached to the surface of the decorative object. Scratches can be made inconspicuous.

  As the base resin of the polypropylene resin and the polypropylene resin composition, various known propylene monomers such as a propylene homopolymer (homopolypropylene), a propylene-α-olefin copolymer, or a propylene block copolymer are mainly used. Various types of raw materials can be selected. Moreover, unless the effects of the present invention are impaired, a filler such as talc may be included for imparting rigidity, or an elastomer may be included for imparting impact resistance. Moreover, you may contain an additive component and another resin component similarly to the polypropylene resin composition which can comprise the decorating film mentioned above.

  Since the decorative molded body in which the decorative film in the present invention is attached to various molded bodies formed in a three-dimensional shape made of a polypropylene resin, VOCs contained in the coating and the adhesive are greatly reduced. It can be suitably used as a home appliance, vehicle (railway, etc.), building material, daily necessities and the like.

[Manufacture of decorative molded bodies]
In the method for producing a decorative molded body of the present invention, the resin molded body and the decorative film are set in a step of preparing the above-described decorative film, a step of preparing the resin molded body, and a chamber box capable of decompression. A step of depressurizing the interior of the chamber box, a step of heat-softening the decorative film, a step of pressing the decorative film against the resin molding, and a step of returning or pressurizing the decompressed chamber box to atmospheric pressure. It is characterized by including.

  Three-dimensional decorative thermoforming sets the object to be decorated and a decorative film in a chamber box that can be decompressed, heat-softens the film in a state where the inside of the chamber box is decompressed, and presses the film against the object to be decorated, The chamber box has a basic process of returning the atmospheric pressure to atmospheric pressure or applying pressure to the surface of the object to be decorated, and applying the film under reduced pressure. As a result, it is possible to obtain a beautiful decorative molded body free from air accumulation. In the production method of the present invention, any known technique can be used as long as the apparatus and conditions are suitable for three-dimensional decorative thermoforming.

  That is, the chamber box may contain all of the object to be decorated, the decorative film, the mechanism for pressing it, the device for heating the decorative film, etc. A plurality of divided items may be used.

Moreover, the mechanism for pressing a decorating object and a decorating film may be any type that moves the decorating object, moves the decorating film, or moves both.
More specifically, typical molding methods are exemplified below.

  Hereinafter, a method for sticking a decorative film to a decoration object using a three-dimensional decorative thermoforming machine will be exemplarily described with reference to the drawings.

  As shown in FIG. 2, the three-dimensional decorative thermoforming machine of this embodiment includes upper and lower chamber boxes 11 and 12 and thermoforming the decorative film 1 in the two chamber boxes 11 and 12. I am doing so. A vacuum circuit (not shown) and an air circuit (not shown) are respectively connected to the upper and lower chamber boxes 11 and 12.

  Further, a jig 13 for fixing the decorative film 1 is provided between the upper and lower chamber boxes 11 and 12. The lower chamber box 12 is provided with a table 14 that can be raised and lowered, and the resin molded body (decoration target) 5 is set on the table 14 (via a jig or directly). The A heater 15 is incorporated in the upper chamber box 11, and the decorative film 1 is heated by the heater 15. The decoration object 5 can use a propylene-type resin composition as a base | substrate.

  As such a three-dimensional decorative thermoforming machine, a commercially available molding machine (for example, NGF series manufactured by Fuse Vacuum Co., Ltd.) can be used.

  As shown in FIG. 3, first, with the upper and lower chamber boxes 11 and 12 opened, the decoration object 5 is placed on the table 14 in the lower chamber box 12, and the table 14 is lowered. Subsequently, the decorative film 1 is set on the jig 13 for fixing the film between the upper and lower chamber boxes 11 and 12 so that the sealing layer (I) faces the substrate.

  As shown in FIG. 4, after the upper chamber box 11 is lowered and the upper and lower chamber boxes 11 and 12 are joined to close the inside of the boxes, the chamber boxes 11 and 12 are brought into a vacuum suction state, and the heater 15 To heat the decorative film 1.

  After the decoration film 1 is heated and softened, as shown in FIG. 5, the table 14 in the lower chamber box 12 is raised while the inside of the upper and lower chamber boxes 11 and 12 is kept in a vacuum suction state. The decorative film 1 is pressed against the decoration target 5 to cover the decoration target 5. Further, as shown in FIG. 6, the decorative film 1 is brought into close contact with the decoration object 5 with a larger force by opening the upper chamber box 11 under atmospheric pressure or supplying compressed air from a pressurized air tank.

  Subsequently, the interiors of the upper and lower chamber boxes 11 and 12 are opened to atmospheric pressure, and the decorative molded body 6 is taken out from the lower chamber box 12. Finally, as illustrated in FIG. 7, an unnecessary edge of the decorative film 1 around the decorative molded body 6 is trimmed.

(Molding condition)
The pressure in the chamber boxes 11 and 12 may be reduced so long as no air is trapped, and the pressure in the chamber boxes 11 and 12 is 10 kPa or less, preferably 3 kPa, more preferably 1 kPa or less.

  Moreover, in the two chamber boxes 11 and 12 divided | segmented up and down by the decorating film 1, if the pressure in the chamber box 11 and 12 by the side to which the decorating object 5 and the decorating film 1 are affixed is this range, The draw down of the decorative film 1 can also be suppressed by changing the pressure of the upper and lower chamber boxes 11 and 12.

  At this time, a film made of a general polypropylene resin may be greatly deformed or broken by a slight pressure fluctuation due to a decrease in viscosity during heating.

  The decorative film 1 of the present invention is not only difficult to draw down, but also has resistance to film deformation due to pressure fluctuations.

  The heating of the decorative film 1 is controlled by the heater temperature (output) and the heating time. It is also possible to measure the surface temperature of the film with a thermometer such as a radiation thermometer and use it as a guideline for appropriate conditions.

  In the present invention, in order to attach the polypropylene decorative film 1 to the decorative object 5 made of polypropylene resin, it is necessary that the surface of the resin molded body 5 and the decorative film 1 are sufficiently softened or melted.

  Therefore, the heater temperature needs to be higher than the melting temperature of the polypropylene resin constituting the decorating object 5 and the polypropylene resin constituting the decorating film 1. The heater temperature is preferably 160 ° C. or higher, more preferably 180 ° C. or higher, and most preferably 200 ° C. or higher.

  The higher the heater temperature, the shorter the time required for heating. However, until the interior of the decorative film 1 (or the surface opposite to the heater when the heater is installed only on one side) is sufficiently heated, If the temperature of the resin is too high, the moldability is deteriorated and the resin is thermally deteriorated. Therefore, the heater temperature is preferably 500 ° C. or lower, more preferably 450 ° C. or lower, most preferably 400 ° C. It is as follows.

Although an appropriate heating time varies depending on the heater temperature, it is preferable that the polypropylene-based decorative film is heated and heated for a period of time before the start of rebound called spring back or for a time longer than that.
In other words, the decorative film heated by the heater expands by heating from the solid state and sags once with the melting of the crystal. However, after the spring back, the film is completely melted and the molecules are sufficiently relaxed, so that sufficient adhesion strength can be obtained.
Furthermore, the decorative film of the present invention can surprisingly strongly adhere to the substrate even if it is subjected to decorative thermoforming before the end of rebounding, and has a great effect in suppressing wrinkles.

  On the other hand, if the heating time is too long, the film hangs down due to its own weight or deforms due to the pressure difference between the upper and lower chamber boxes 11 and 12, so that the heating time may be less than 120 seconds after the end of the springback. preferable.

  In the case of decorating a complex shaped article having irregularities or achieving higher adhesion, it is preferable to supply compressed air when the decorative film is brought into close contact with the substrate. The pressure in the upper chamber box 11 when compressed air is introduced is 150 kPa or more, preferably 200 kPa or more, more preferably 250 kPa or more. Although there is no particular limitation on the upper limit, 450 kPa or less, preferably 400 kPa or less is preferable because the device may be damaged if the pressure is too high.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

1. Measuring methods of various physical properties (i) Melt flow rate (MFR)
In accordance with ISO 1133: 1997 Conditions M, measurement was performed at 230 ° C. and a load of 2.16 kg. The unit is g / 10 minutes.

(Ii) Melting peak temperature (melting point)
Using a differential scanning calorimeter (DSC), once the temperature was raised to 200 ° C. and held for 10 minutes, the temperature was lowered to 40 ° C. at a temperature lowering rate of 10 ° C./min, and again at a temperature rising rate of 10 ° C./min. The temperature at the top of the endothermic peak when measured was taken as the melting peak temperature (melting point). The unit is ° C.

(Iii) Density The density of the ethylene-α-olefin random copolymer (B) was measured according to the density gradient tube method of JIS K7112: 1999.

(Iv) Ethylene content [E (B)]
The ethylene content [E (B)] of the ethylene-α-olefin random copolymer (B) was determined from the integrated intensity obtained by ¹³ C-NMR measurement based on the method described above. Sample preparation and measurement conditions are as follows.
200 mg of the sample ethylene-α-olefin random copolymer (B) was mixed with o-dichlorobenzene / deuterated benzene bromide (C ₆ D ₅ Br) = 4/1 (volume ratio) 2.4 ml and chemical shift. The sample was dissolved together with hexamethyldisiloxane as a reference substance in an NMR sample tube having an inner diameter of 10 mmφ.
The NMR measurement was performed using an AV400 NMR apparatus manufactured by Bruker BioSpin Co., Ltd. equipped with a 10 mmφ cryoprobe.
^{The 13} C-NMR measurement conditions were as follows: the sample temperature was 120 ° C., the pulse angle was 90 °, the pulse interval was 20 seconds, and the number of integrations was 512 times.

2. Materials used (1) Polypropylene resin The following polypropylene resins were used.
(A-1): Propylene-α-olefin copolymer (MFR (A) = 7 g / 10 min, Tm (A) = 146 ° C.), manufactured by Nippon Polypro Co., Ltd., trade name “NOVATEC (registered trademark) FW3GT "
(A-2): Propylene homopolymer (MFR (A) = 10 g / 10 min, Tm (A) = 161 ° C.), manufactured by Nippon Polypro Co., Ltd., trade name “NOVATEC (registered trademark) FA3KM”

(2) Ethylene-α-olefin random copolymer The following ethylene-α-olefin random copolymer was used.
(B-1): ethylene-butene random copolymer (MFR (B) = 6.8 g / 10 min, Tm (B) = 66 ° C., density = 0.85 g / cm ³ , ethylene content [E (B) ] = 84 wt%): Mitsui Chemicals, trade name “Toughmer A4085S”
(B-2): ethylene-butene random copolymer (MFR (B) = 7.0 g / 10 min, Tm (B) = 47 ° C., density = 0.860 g / cm ³ , ethylene content [E (B) ] = 73 wt%): Mitsui Chemicals, trade name “Tuffmer A4050S”
(B-3): ethylene-octene random copolymer (MFR (B) = 2.0 g / 10 min, Tm (B) = 77 ° C., density = 0.85 g / cm ³ , ethylene content [E (B) ] = 85 wt%): DuPont Dow, trade name “Engage EG8003”
(B-4): ethylene-octene random copolymer (MFR (B) = 2.0 g / 10 min, Tm (B) = 38 ° C., density = 0.860 g / cm ³ , ethylene content [E (B) ] = 75 wt%): DuPont Dow, trade name “engage EG 8842”
(B-5): ethylene-hexene random copolymer (MFR (B) = 3.5 g / 10 min, Tm (B) = 60 ° C., density = 0.880 g / cm ³ , ethylene content [E (B) ] = 76 wt%): manufactured by Nippon Polyethylene Co., Ltd., trade name “Kernel KS340T”
(B-6): ethylene-propylene random copolymer (MFR (B) = 7.0 g / 10 min, Tm (B) = 38 ° C., density = 0.860 g / cm ³ , ethylene content [E (B) ] = 73 wt%): Product name “Toughmer P0280” manufactured by Mitsui Chemicals, Inc.

(3) Acrylic resin (C)
(C-1): Polymethylmethacrylate resin film, manufactured by Mitsubishi Rayon Co., Ltd., trade name “Acryprene (registered trademark) HBS010P, film thickness 75 μm”

(4) Adhesive resin (D)
(D-1): Maleic anhydride modified polyolefin (MFR (D) = 7 g / 10 min), manufactured by Mitsubishi Chemical Corporation, trade name “Modic AP (registered trademark) F534A”
(D-2): Maleic anhydride modified polyolefin (MFR (D) = 1.6 g / 10 min), manufactured by Mitsubishi Chemical Corporation, trade name “Modic AP (registered trademark) F532”

3. Production of Resin Molded Body (Substrate) An injection molded body was obtained by the following method using the following polypropylene resins (X-1) to (X-3).
(X-1): Propylene homopolymer (MFR = 40 g / 10 min, Tm = 165 ° C.), manufactured by Nippon Polypro Co., Ltd., trade name “NOVATEC (registered trademark) MA04H”
(X-2): Propylene ethylene block copolymer (MFR = 30 g / 10 min, Tm = 164 ° C.), manufactured by Nippon Polypro Co., Ltd., trade name “Novatech (registered trademark) NBC03HR”
(X-3): 60% by weight of polypropylene resin (X-2), 20% by weight of EBR (Tafmer (registered trademark) A0550S manufactured by Mitsui Chemicals, Inc.) with MFR = 1.0, inorganic filler (Nippon Talc) TALC P-6 manufactured by Co., Ltd. 20 wt% blended polypropylene resin composition injection molding machine: “IS100GN” manufactured by Toshiba Machine Co., Ltd. Clamping pressure 100 ton Cylinder temperature: 200 ° C.
Mold temperature: 40 ℃
Injection mold: Width x height x thickness = 120 mm x 120 mm x 3 mm flat plate condition adjustment: hold for 5 days in a constant temperature and humidity chamber at a temperature of 23 ° C and a humidity of 50% RH

Example 1
-Manufacture of a decorative film 2 having a lip opening of 0.8 mm and a die width of 400 mm, to which a sealing layer extruder-1 having a diameter of 30 mm (diameter) and an adhesive layer extruder-2 having a diameter of 40 mm (diameter) are connected. A seed two-layer T die was used. An adhesive layer obtained by blending a polypropylene resin (A-1) and an ethylene-α-olefin random copolymer (B-1) so as to have a weight ratio of 85:15 to the seal layer extruder-1 Adhesive resin (D-1) is charged into extruder 2 for resin, the resin temperature is 240 ° C., the discharge rate of extruder 1 for seal layer is 4 kg / h, and the discharge rate of extruder 2 for adhesive layer Was melt extruded under the condition of 8 kg / h. The melt-extruded film is cooled and solidified while being pressed against the first roll rotating at 80 ° C. at 3 m / min with an air knife so that the seal layer is in contact, and a 50 μm thick seal layer and a 100 μm thick adhesive layer are laminated. A two-layer unstretched film was obtained.
The obtained unstretched film and the film (C-1) made of the acrylic resin (C) were cut out with a width of 250 mm and a length of 1000 mm, respectively, so that the longitudinal direction was the MD direction of the film. The cut acrylic film and the unstretched adhesive layer of the cut unstretched film were stacked so that they were in contact with each other, and were integrated under the following conditions using a heat laminator to obtain a decorative film. The thermal lamination conditions are as follows.
Thermal laminator: “Small table laminator” manufactured by Tester Sangyo Co., Ltd.
Heating condition: acrylic film contact surface, 130 ° C
Seal layer contact surface, 23 ° C
Pressure condition: 1.5kgf / m
Line speed: 0.5m / min

-Three-dimensional decoration thermoforming As the resin molding (base | substrate) 5, the injection molding which consists of the polypropylene resin (X-1) obtained by the above was used.
As a three-dimensional decorative thermoforming apparatus, “NGF-0406-SW” manufactured by Fuse Vacuum Co., Ltd. was used. As shown in FIGS. 2 to 7, the decorative film 1 was set on a film fixing jig 13 having an opening size of 210 mm × 300 mm so that the seal layer faces the substrate. The resin molded body (base body) 5 is placed on a table 14 positioned below the film fixing jig 13 and placed on a sample mounting table having a height of 20 mm, “Nystack NW-K15” manufactured by Nichiban Co., Ltd. ”Pasted through. The film fixing jig 13 and the table 14 were installed in the chamber boxes 11 and 12, the chamber box was closed, and the chamber boxes 11 and 12 were sealed. The chamber box is divided up and down via the decorative film 1. In the state which vacuum-sucked the upper and lower boxes and reduced pressure from atmospheric pressure (101.3 kPa) to 1.0 kPa, the far-infrared heater 15 installed on the upper chamber box 11 is started at an output of 80%, and the decorative film 1 is Heated. Vacuum suction was continued during heating, and the pressure was finally reduced to 0.1 kPa. The decorative film 1 is heated to sag temporarily, and then the table 14 installed in the lower chamber box 12 is moved upward after 25 seconds from the end of the springback phenomenon, and the resin molded body is moved upward. (Substrate) 5 was pressed against the decorative film 1, and immediately after that, compressed air was fed so that the pressure in the upper chamber box 11 was 270 kPa, thereby bringing the resin molded body (substrate) 5 and the decorative film 1 into close contact. In this way, a three-dimensional decorative thermoformed product 6 in which the decorative film 1 was adhered to the upper surface and the side surface of the resin molded body (substrate) 5 was obtained.

-Physical property evaluation (1) Evaluation of thermoformability (appearance of decorative molded body)
The drawdown state of the decorative film at the time of three-dimensional decorative thermoforming, and the sticking state of the decorative film of the decorative molded body in which the decorative film is attached to the base are visually observed, and the criteria shown below It was evaluated with.
○: At the time of three-dimensional decorative thermoforming, the decorative film did not draw down, and the contact between the substrate and the decorative film was made simultaneously on the entire contact surface, so contact unevenness did not occur and it was evenly attached ing.
X: Since the decorative film was drawn down during three-dimensional decorative thermoforming, contact unevenness occurred on the entire surface of the substrate.

(2) Adhesive strength between resin molded body (base) and decorative film “Craft adhesive tape No. 712N” manufactured by Nitoms Co., Ltd. was cut into a width of 75 mm and a length of 120 mm, from the end of the resin molded body (base). A masking process was applied to a resin molded body (substrate) in a range of 75 mm × 120 mm (substrate surface exposed portion was 45 mm wide and 120 mm long). It installed in the three-dimensional decorative thermoforming apparatus NGF-0406-SW so that the masking surface of the resin molded body (substrate) was in contact with the decorative film, and three-dimensional decorative thermoforming was performed.

  The decorative film surface of the obtained decorative molded body was cut to the substrate surface with a width of 10 mm using a cutter in a direction perpendicular to the longitudinal direction of the adhesive tape to prepare a test piece. In the obtained test piece, the bonding surface between the base and the decorative film is 10 mm wide × 45 mm long. Attach to the tensile tester so that the base part of the test piece and the decorative film part are 180 °, measure the 180 ° peel strength of the adhesive surface at a tensile speed of 200 mm / min, and take the maximum strength at the time of peeling or breaking (N / 10 mm) was measured 5 times, and the average strength was defined as the adhesive strength.

(3) Gloss The gloss (gross) near the center of the decorative molded body on which the decorative film was stuck was measured using a Nippon Denshoku Industries Co., Ltd. GLOSS meter Gloss Meter VG2000 at an incident angle of 60 °. . The measuring method was based on JIS K7105-1981.

  Table 1 shows the results of evaluating physical properties of the obtained decorative molded body and the like. The obtained decorative molded body was excellent in appearance and adhesive strength.

Example 2
In the production of the decorative film of Example 1, evaluation was performed in the same manner as in Example 1 except that the ethylene-α-olefin random copolymer used for the seal layer was changed to (B-2). The evaluation results are shown in Table 1. The obtained decorative molded body was excellent in appearance and adhesive strength.

Example 3
In the production of the decorative film of Example 1, evaluation was performed in the same manner as in Example 1 except that the ethylene-α-olefin random copolymer used for the seal layer was changed to (B-3). The evaluation results are shown in Table 1. The obtained decorative molded body was excellent in appearance and adhesive strength.

Example 4
In the production of the decorative film of Example 1, evaluation was performed in the same manner as in Example 1 except that the ethylene-α-olefin random copolymer used in the seal layer was changed to (B-4). The evaluation results are shown in Table 1. The obtained decorative molded body was excellent in appearance and adhesive strength.

Example 5
In the production of the decorative film of Example 1, evaluation was performed in the same manner as in Example 1 except that the ethylene-α-olefin random copolymer used for the seal layer was changed to (B-5). The evaluation results are shown in Table 1. The obtained decorative molded body was excellent in appearance and adhesive strength.

Example 6
In the production of the decorative film of Example 1, evaluation was performed in the same manner as in Example 1 except that the ethylene-α-olefin random copolymer used for the seal layer was changed to (B-6). The evaluation results are shown in Table 1. The obtained decorative molded body was excellent in appearance and adhesive strength.

Example 7
In the production of the decorative film of Example 1, the Example was used except that the blending ratio of the polypropylene resin (A-1) and the ethylene-α-olefin random copolymer (B-1) was set to 70:30. Evaluation was performed in the same manner as in 1. The evaluation results are shown in Table 1. The obtained decorative molded body was excellent in appearance and adhesive strength.

Example 8
In the production of the decorative film of Example 1, Example except that the blending ratio of the polypropylene resin (A-1) and the ethylene-α-olefin random copolymer (B-1) was 30:70. Evaluation was performed in the same manner as in 1. The evaluation results are shown in Table 1. The obtained decorative molded body was excellent in appearance and adhesive strength.

Example 9
In the production of the decorative film of Example 1, evaluation was performed in the same manner as in Example 1 except that the adhesive resin used in the adhesive layer was changed to (D-2). The evaluation results are shown in Table 1. The obtained decorative molded body was excellent in appearance and adhesive strength.

Example 10
In the production of the decorative film of Example 1, evaluation was performed in the same manner as in Example 1 except that the polypropylene resin used for the seal layer was changed to (A-2). The evaluation results are shown in Table 1. The obtained decorative molded body was excellent in appearance and adhesive strength.

Comparative Example 1
In the production of the decorative film of Example 1, Example 1 was used except that only the polypropylene resin (A-1) was used without blending the ethylene-α-olefin random copolymer (B) in the seal layer. Evaluation was performed in the same manner. The evaluation results are shown in Table 1.
Since the ethylene-α-olefin random copolymer (B) was not included in the seal layer, the adhesive strength was poor.

Comparative Example 2
In the three-dimensional decorative thermoforming of Comparative Example 1, the evaluation was performed in the same manner as in Example 1 except that the heating time after springback was changed from 25 seconds to 40 seconds. The evaluation results are shown in Table 1.
Because the heating time was long, the decorative film was in contact with the substrate in a state where the decorative film was hanging down due to its own weight. Therefore, contact unevenness occurred in the entire decorative molded body, and the appearance was poor.

Comparative Example 3
In the production of the decorative film of Example 1, evaluation was performed in the same manner as in Example 1 except that only the acrylic film (C-1) was used. The evaluation results are shown in Table 1.
Since the adhesive layer was not laminated on the decorative film, it did not adhere to the substrate.

Example 11
In the three-dimensional decorative thermoforming of Example 1, evaluation was performed in the same manner as in Example 1 except that the base was changed to an injection-molded body using resin (X-2). The obtained results are shown in Table 1.
The obtained decorative molded body was excellent in appearance and adhesive strength.

Example 12
In the three-dimensional decorative thermoforming of Example 1, evaluation was performed in the same manner as in Example 1 except that the base was changed to an injection-molded body using resin (X-3). The obtained results are shown in Table 1.
The obtained decorative molded body was excellent in appearance and adhesive strength.

  According to the present invention, sufficient adhesive strength and product appearance can be achieved at the same time, and it is possible to reduce product defects by making the scratches on the substrate inconspicuous, and further used for three-dimensional decorative thermoforming that facilitates recycling. A decorative film and a method for producing a decorative molded body using the same are provided.

1 decorative film 2 layers (II)
3 Sealing layer (I)
4 Print layer (IV)
5 Resin molded body (decoration object, substrate)
6 Decorative molded body 7 Adhesive layer (III)
11 Upper chamber box 12 Lower chamber box 13 Jig 14 Table 15 Heater

Claims (6)

A decorative film for sticking by thermoforming on a resin molded body,
The decorative film contains a polypropylene resin (A) and an ethylene-α-olefin random copolymer (B) as main components, and the polypropylene resin (A) and an ethylene-α-olefin random copolymer (B). And a weight ratio of 97: 3 to 5:95, a sealing layer (I) made of a resin composition, a layer (II) made of an acrylic resin (C), and a sealing layer (I) and a layer (II) Including an adhesive layer (III) made of an adhesive resin (D),
The polypropylene resin (A) satisfies the following requirement (a1),
The said ethylene-alpha-olefin random copolymer (B) satisfies the following requirements (b1)-(b3), The decorative film characterized by the above-mentioned.
(A1) Melt flow rate (230 ° C., 2.16 kg load) (MFR (A)) exceeds 0.5 g / 10 min.
(B1) The ethylene content [E (B)] is 65% by weight or more.
(B2) The density is 0.850 to 0.950 g / cm ³ .
(B3) Melt flow rate (230 ° C., 2.16 kg load) (MFR (B)) is 0.1 to 100 g / 10 min. The decorative film according to claim 1, wherein the ethylene-α-olefin random copolymer (B) satisfies the following requirement (b4).
(B4) The melting peak temperature (Tm (B)) is 30 to 130 ° C. The decorative film according to claim 1 or 2, wherein the ethylene-α-olefin random copolymer (B) satisfies the following requirement (b5).
(B5) A random copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms.   The adhesive resin (D) is a polyolefin resin having a polar functional group containing at least one hetero atom, and its MFR (230 ° C., 2.16 kg load) (MFR (D)) is 100 g / 10 min. It is the polyolefin resin which is the following, The decorating film in any one of Claims 1-3 characterized by the above-mentioned.   The step of preparing the decorative film according to any one of claims 1 to 4, the step of preparing a resin molded body, the step of setting the resin molded body and the decorative film in a chamber box capable of decompression, Including depressurizing the inside of the chamber box, heating and softening the decorative film, pressing the decorative film against the resin molding, and returning or pressurizing the decompressed chamber box to atmospheric pressure. A method for producing a decorative molded body characterized by the above.   The method for producing a decorative molded body according to claim 5, wherein the resin molded body is made of a propylene-based resin composition.